Insulation wrapping machine



Feb. 6, 1962 c. R. NAVIKAS INSULATION WRAPPING MACHINE Filed April 13,1959 INVENTOR. CHARLES R. NAVIKAS arromvn 3,019,573 INSULATION PINGMAt'JI-IINE Charles R. Navikas, Speedway, Ind, assignor to UlllOl'lCarbide Corporation, a corporation of New York Filed Apr. 13, 1959, Ser.No. 805,793 14 Claims. (Cl. 53--27) This invention relates to a methodand apparatus for applying a composite insulating material about acontainer, particularly the multi-layer insulating material employed inthe solid-in-vacuum type insulation described in the copendingapplication of L. C. Matsch, Serial No. 597,947, filed July 16, 1956.

The aforesaid patent application discloses a multi-layer insulatingmaterial comprising generally alternating layers of a thin, flexiblemetal foil, such as aluminum, and a porous fibrous sheeting of lowconductive material, such as glass fiber, which are confo-rmably wrappedaround a cylinder under suitable tension.

It is possible to hand wrap the sheetings of foil and fibrous materialaround a container and end up with an insulation wrapping which willperform satisfactorily in the vacuum insulating space of a double walledcontainer. However, such a procedure is not only time consuming andcumbersome, and in some instances not susceptible of practice because ofthe relative magnitudes of the container sizes and weights involved, butis relatively expensive.

The tension applied to the wrapped composite insulation is an essentialvariable which may tend to downgrade the insuiating system. For example,as explained in the aforesaid patent application, tightening of theinsulation wrapping causes the fibrous sheeting to be compressed andincreases the effective path of solid conduction therethrough. On theother hand, wrapping the insulation too loosely decreases the number offoil turns and increases heat leak by radiation therethrough. Optimumresults obtain somewhere between these extremes.

Furthermore, aluminum foil must be handled with great care as it maytear because of uneven or undue tension or other reasons. Applying thesame tension to the foil and to the fiber sheeting is furthermoreundesirable, because the fiber sheeting is considerably weaker intension than the foil. It is also a problem to apply a suitable numberof turns of composite insulation to provide an insulation wrapping of aprescribed thickness. In addition, there is a problem in handling ordisposing of the paper backing, such as found in glass fiber rolls,during the process of wrapping the fiber sheet and aluminum foil arounda container.

For these and other reasons, it is desirable to provide a reliable meansfor achieving a satisfactory wrapping of composite insulation about acontainer without encountering the aforementioned difiicultics.

It is, therefore, an important object of the present invention toprovide an improved method and apparatus for wrapping a container withcomposite layers of insulating material that results in a suitable andsubstantially uniform tension throughout the insulation wrapping.

it is another object of the invention to provide a convenient andeconomical method and apparatus for applying a wrapping of compositelayers of insulation onto a container in a manner that is effective andnot damaging to the composite layers of insulation.

Other objects, features and advantages of the invention will be apparentfrom the following detailed description of a preferred embodimentthereof, taken in conjunction with the attached drawings in which:

FIG. 1 is a schematic diagram showing an insulation wrapping machineembodying the principles of the invention FIG. 2 is an isometric view ofa preferred modification of a wrapping machine showing the drivingmechanism therefor; and

FIG. 3 is an enlarged fragment of the view shown in FIG. 2 andillustrating the operation of the foil piercing 5 roll.

The preferred pnactice of the invention will be described in terms ofwrapping a container with a composite insulation of aluminum foil andglass fiber sheeting. It is to be understood, however, that suchdescription is presented as illustrative only and that it is notintended to limit the scope of the invention.

Shown in FIG. 1 is a preferred diagrammatic illustration of aninsulation wrapping machine embodying the principles of the presentinvention comprising a pair of frame members it only one being shown,upon which are mounted a metal foil carrier roll 12 from which aluminumfoil 14 is supplied, a fiber insulation stock roll 16 from which glassfiber sheeting 18 is fed, and a wind-up drum or container 2%), which isthe vessel to be insulated, about which a composite of the aluminum foil14 and the glass fiber sheeting 18 is Wound. The roll of aluminum foil14 is mounted on the carrier roll 12 so that it will unroll and passaround the container 2% where it is superimposed upon glass fiber sheet18 and wrapped there with around the container.

The glass fiber sheet material 1% is commercially available and usuallysold in rolled sheet form with a paper backing 26. Since the paperbacking is not used in the formation of the insulation product, it isseparated and collected on paper roll 28 as the fiber insulation roll inis unwound. Glass fiber sheet 18 is advanced from roll 16 and is fedonto the container 20 where it meets foil 14 and is plied between thelayers of foil wrapping.

In the preferred modification of the invention shown in FIG. 2, meansare provided for piercing the metal foil in order to form passagesthrough the otherwise vaporimpervious barrier. This aids in completeevacuation of the insulation when it is installed in a container shellin the manner illustrated in the aforesaid application. To this end, aperforating roll 22 is rotatably mounted in the frame members it betweenthe foil carrying roll 12 and the container 29. The aluminum foil 14 onroll 12 passes around the perforating roll 22 and is then conveyed tothe container 2a. The surface of the perforating roller 22 is providedwith a plurality of generally radially extending projections 24preferably arranged in helical rows of spirals. This arrangement permitspiercing at any given instant a minimum number of uniformly spaced holesacross the width of the metal foil 14- without significantly affectingthe tensile strength of the foil. In addition, the helical arrangementaffords means for providing a suitable number of perforations in thefoil 14 without noticeably reducing the shielding properties thereof.

The enlarged view of the piercing roll shown in FIG. 3 illustrates thepreferred configuration for the projections 24. Projections 24 should bebevelled with the leading bevel edge first contacting the foil. Thispierces a hole 25 in the foil 14, and folds over the struck out portionor flap 27, thereby preventing it from flapping back and closing thehole.

Means are provided for driving the container 20 and the feed rolls 12,16 and paper roll 28. For this purpose, the container 20 is rotatablymounted between head stock and tailstock supports 30, 39 extending fromthe frame members 10. Supports 30, 30 may for example be suitably springloaded by means not illustrated but wellknown to those skilled in theart, for ease in positioning the container therebetween. Headstock 30 isrotatably driven by a chain belt 32 from a pulley 34A. Pulley 34- ismounted on a shaft 36 journalled in a bracket (not shown) on the machineframe. It is driven from a speed reducing gear box 38 connected to amotor 40.

The metal foil carrier roll 12 is connected to the paper collecting roll28 through a pulley drive comprising a driver pulley 42 mounted on theaxis 13 of roll 12;, an intermediate speed regulating mechanism 44suitably rotatably mounted in the frame 10, and a pulley belt 46 oversaid pulleys 42 and speed regulating mechanism 44. By means of a belt48, the speed regulating mechanism 44- drives a driven pulley 50 mountedon the axis 2? of paper roll 28. As container 20 rotates, it pulls metalfoil 14 from roll 12 and causes rotation of roll 12. Rotation of roll12, in turn, causes paper roll 28 to rotate and pull paper backing 26from the fibrous material 18. This causes glass fiber roll 16 to rotateand feed fibrous sheeting 18 toward container 2%.

The speed regulating mechanism 44 between driver pulley 42 and drivenpulley 50 provides the means for adjustably controlling the relativesurface speeds of paper roll 28 and foil roll 12, such means beingwell-known by those skilled in the art. Preferably, the surface speed ofpaper sheeting 26 is adjusted to be slightly greater than the surfacespeed of foil 14. This removes substantially all the tension from thefibrous material 18 which is inherently a weak material and could easilyseparate under tension. Consequently, the fibrous sheeting 18 islitterally laid on the container 20 without substantial tension. Thecomposite of aluminum foil and fibrous layer insulation is wound up intoa roll under moderate tension about the container 20. Tension of themetal foil is controlled by means of a Prony brake or other adjustablefriction brake 54 located on the axis 13 of the roll 32.

The method and apparatus of the invention can be performed and operatedby either one or two men, or can be fully automated if so desired. Afavorable test of the invention was conducted under the followingconditions:

A roll of .0004" thickness aluminum foil and 54" in width, mounted onroll 12, was manually unrolled to provide a sufiicient length ofaluminum foil sheeting 14 to pass around the perforating roll 22 andextend up to the container 20. The end of the aluminum foil 14 Was tapedto the cylindrical surface of the container 20, the outside diameter ofwhich was approximately 15 /2. Rotation of the container 20 wasgradually started by a first operator by means of a suitable control onmotor 40. After approximately one-half turn of foil had been wrappedaround the container, a second operator fed the free end of the fibersheet 18, 57 in width and A thick, from fiber roll 16 into the nipbetween the overlying foil 14 and container 20 as shown in FIG. 2. Thebacking paper 26 was taped to the backing paper roll 28.

The second operator firmly grasped roll 16 to halt its rotation, andrelaxed his hold when necessary to control the feed of the fibersheeting 18 during the starting period as it was introduced between thelayers of aluminum foil. This control is possible due to the fact thatthe fiber roll 16 is mounted between two cone type rolls. Once the fibersheeting had been gripped by foil wrapping, the second operatormanipulated the friction brake 54 to achieve the proper tension on foil14 and adjusted the speed of the fiber sheet 18 by means of the speedregulating mechanism 44.

It will be appreciated that care must be exercised in the feeding of thefiber sheeting 18 that no tension is applied thereto. For this purpose,and in order that the operator may have some leeway in adjusting thespeed regulating mechanism 44 or the friction brake 54, a liberal amountof slack or sag must be provided in the fiber sheeting 18 as illustratedin the drawings. This slack is an excellent indication to the operatorthat the fiber sheeting is not under tension and amply warns him when anadjustment is necessary.

After the initial feeding of fiber and foil, the first operatorcontrolled the speed of rotation of the container 20 and observed thefoil 14 for rips or tears, and the second operator carefully watched theslack in the fiber sheeting 18 and properly adjusted the speedregulating mechanism 44 to compensate for changes in the sag of thefiber sheeting. During this period, there was no tension on the fibersheeting 18, tension being solely on the foil 14 and the backing paper26. The number of turns of composite insulation was suitably recorded,for example, by a rod 58 extending radially from the supporting shaft ofheadstock 3t and terminating in an ofiset arm til) which slides over arecording tab or detent (not shown) fixed to the frame 10.

After 25 layers of composite insulation had been ap plied to thewrapping machine, the machine was stopped, and the circumference of theinsulation was measured. The outside diameter of the insulation was thencalculated to be 19". This dimension afforded sufiicient clearance forthe insulation wrapped container to be inserted into an outer containerwhose inside diameter was approximately 19 /2.

One extra turn of aluminum foil was applied to the container by firmlyholding roll 16 and rotating container 20, thereby placing fibersheeting 18 under tension and causing it to tear in a transversedirection. To prevent the loosening and unrolling of the insulationwrapping, the end of the aluminum foil was taped in place. Followingthis, the marginal portions of the composite insulation were folded inat both ends of the container 2t) and taped in place. This was carefullydone to preserve the alternate layers of foil and fibrous sheeting "andto avoid the possibility of the foil contacting the container. In thisrespect, the wider fibrous sheeting (57" in Width) also preserved thespacing of the foil (54" in Width). The wrapped container 20 was thenremoved from the wrapping machine and placed in a production line forassembly inside an outer container (not shown) to subsequently providethe insulation substantially shown and described in the aforesaidcopending application.

It will be understood that although the insulation wrapping machine andinsulation wrapping method of the invention have been described withreference to wrapping a cylindrically shaped container, the invention isnot intended to be so limited. Modifications and variations may beeffected without departing from the spirit and scope of the invention.

What is claimed is:

1. In a wrapping machine for rolling a composite metal foil-fibroussheeting layer type insulation about a container, 2. machine frame forrotatably supporting said container, a foil .roll and a fibrous sheetingroll rotatably mounted in said frame, rotating means for controllablyrotating said container, drive means for rotating said fibrous sheetingroll at a speed correlated to said container speed to feed fibroussheeting thereto with slack, and means for rotating said foil roll toroll foil around said container under an adjustably uniform tension.

2. In a wrapping machine for rolling a composite metal foil-fibroussheeting layer type insulation about a container, a machine frame forrotatably supporting said container, a foil roll rotatably mounted insaid frame, a. fibrous sheeting roll, including a paper backing,rotatably mounted in said frame, rotating means for controllablyrotating said container, a paper roll adapted to pull backing paper ofisaid fibrous sheeting roll, drive means for rotating said paper roll ata speed to turn said fibrous sheeting roll at a speed correlated to saidcontainer speed to feed fibrous sheeting thereto with slack, and meansfor rotating said foil roll to roll foil around said container under anadjustably uniform tension.

3. Apparatus according to claim 2, said drive means being disposedbetween said metal foil roll and said paper collection roll andincluding a speed regulating mechanism for adjustably controlling therelative surface speeds of said metal foil and said paper backing tosubstantially remove all tension from said fibrous sheeting during itsdelivery to said container.

4. Apparatus according to claim 1, a piercing roll rotatably mountedbetween said metal foil roll and said container, and a multiplicity ofprojections extending sub stantially radially outwardly from the surfaceof said piercing roll for piercing holes in said metal foil during itspassage therepast.

5. Apparatus according to claim 2, a piercing roll rotatably mountedbetween said metal foil roll and said container, and a multiplicity ofprojections extending substantially radially outwardly from the surfaceof said piercing roll for piercing holes in said metal foil during itspassage therepast.

6. Apparatus according to claim 3, a piercing roll rotatably mountedbetween said metal foil roll and said container, and a multiplicity ofprojections extending substantially radially outwardly from the surfaceof said piercing roll for piercing holes in said metal foil during itspassage therepast.

7. Apparatus according to claim 1, a piercing roll rotatably mountedbetween said metal foil roll and said container, and a multiplicity ofprojections extending substantially radially outwardly from the surfaceof said piercing roll for piercing holes in said metal foil during itspassage therepast.

8. Apparatus according to claim 4, said projections being arranged inhelical rows around said piercing roll, said projection being linearlyuniformly spaced in said rows.

9. Apparatus according to claim 4, each of said projections having abevelled end so constructed and arranged that the leading edge of thebevel first contacts the metal foil to be pierced.

10. Apparatus for wrapping a composite metal foilfibrous sheeting layertype insulation about a container comprising a roll of metal foil forfeeding metal foil to said container, said container and said metal foilroll being rotatably mounted on relatively fixed parallel axes, a rollof fibrous sheeting rotatably mounted parallel to said roll of metalfoil for feeding fibrous sheeting directly to said container, drivingmeans for rotating said container whereby the foil runs over saidcontainer and is held against the surface thereof to provide overlyinglayers of foil thereon, and a drive and speed regulating means to rotatesaid roll of fibrous sheeting and deliver the sheeting therefrom betweenthe overlying layers of foil on said container without substantialtension on said fibrous sheeting.

11. Apparatus for wrapping a composite metal foilfibrous sheeting layertype insulation about a container comprising a roll of metal foil forfeeding metal foil to said container, said container and said metal foilroll Q being rotatably mounted on relatively fixed parallel axes, a rollof paper backed fibrous sheeting rotatably mounted parallel to said rollof metal foil for feeding fibrous sheeting directly to said container, apaper collection roll rotatably mounted parallel to said fibroussheeting roll for collecting the paper backing from the fibrous sheeting roll, driving means for rotating said container whereby the foilruns over said container and is held against the surface thereof toprovide overlying layers of foil thereon, a drive to rotate said papercollection roll, whereby the rotation of said paper collection rollwithdraws paper backing from said roll of paper backed fibrous sheetingto rotate said roll of fibrous sheeting and deliver the sheetingtherefrom between the overlying layers of foil on said container withoutsubstantial tension on said fibrous sheeting.

12. A process for wrapping a composite metal foilfibrous sheeting layertype insulation about a container comprising attaching the end of ametal foil to the outer surface of a container, rotatably driving saidcontainer to wrap overlying layers of said metal foil thereon,delivering fibrous sheeting to said container between the overlyinglayers of foil and providing a sufiicient slack in said fibrous sheetingprior to delivery between the overlying layers of foil, thereby toremove substantially all tension from said fibrous sheeting.

13. A process according to claim 12, and piercing said metal foil beforewrapping around said container.

14. A process for wrapping a composite metal foilfibrous sheeting layertype insulation about a container comprising attaching the end of ametal foil to the outer surface of a container so that the width of thefoil extends beyond the ends of the container, rotatably driving saidcontainer to wrap overlying layers of said metal foil thereon,delivering fibrous sheeting having a width slightly larger than thewidth of said foil to said container between the overlying layers offoil, and successively folding the marginal portion of said foil andfibrous sheeting about the ends of said container, whereby metal contactbetween adjacent layers of foil in the space adjacent the ends of saidcontainer is avoided.

References Cited in the file of this patent UNITED STATES PATENTS836,241 Camp Nov. 20, 1906 2,111,901 Ness Mar. 22, 1938 2,176,109 RatayOct. 17, 1939 2,649,672 Thompson Aug. 25, 1953 2,848,151 ONeil Aug. 19,1958 2,893,189 Lancaster Jul 7, 1959

